Is Visible node

I have a question about the Is Visible node.I want my schematic to activate when an enemy is inside my camera's view, so is this node the correct one to use?I have a tick schematic attached to the enemy that is

Setting -> Is Visible(the machine object)Visible slot -> dialogue(Enemy is in view)Invisible slot -> dialogue(Enemy is out of view)

The problem is that even if the enemy is out of the camera's view, the success slot still keeps on running.If this is not the right way to use, is makinom capable of it? :)